CN102426436A - Multi-axis numerical control machining post-processing method considering structural error of machine tool - Google Patents

Abstract

The invention provides a multi-axis numerical control machining post-processing method considering a structural error of a machine tool. The method comprises the following steps of: respectively establishing a machine tool motion transformation chain containing no structural error and a machine tool motion transformation chain containing the structural error according to the structure of the machine tool, wherein the machine tool motion transformation chain containing no structural error is used for figuring out ideal motion coordinate of each motion axis of tool motion and the structural error of the machine tool is not taken into consideration in the ideal motion coordinate; and then figuring out the compensating quantity of the ideal motion coordinate by using the machine tool motion transformation chain containing the structural error; and enabling the offset between an actual motion track and a set motion track of the machine tool to fall within an allowed range through compensating the ideal motion coordinate so that the consistency between the actual track and the set track of the tool is assured. According to the invention, the shortcomings in the traditional post-processing method are made up; the multi-axis post-processing containing geometrical structure error of the machine tool can be realized so that the multi-axis numerical control machining post-processing method is helpful to improve the motion precision in the processing process of the machine tool and improve the processing quality of the parts.

Description

The multi-axis numerical control of consideration machine tool structure error is processed rearmounted disposal route

Technical field:

The present invention relates to the multi-axis numerical control manufacture field, specifically is that a kind of multi-axis numerical control is processed rearmounted disposal route.

Background technology:

Along with the development of industries such as national defence, delivery, the energy, key function part such as naval vessel with processing and manufacturings such as screw propeller, airplane intake, wind electricity blades higher demand have been proposed.This type part profile and work profile are complex-shaped, are difficult to the precision that reaches desirable with three-axis numerical control machining tool processing, even can't realize processing, and must adopt the multi-axis numerical control lathe could accomplish processing.

In five-shaft numerical control processing; The rearmounted main task of handling is that the processing cutter spacing track source file that CAM software generates is converted into the acceptable numerical control NC of specific lathe code; Usually suppose in the at present common Post-processing Algorithm that each moving component of lathe is on the desirable geometric position; Do not consider the position and the attitude misalignment that exist between the machine tool motion component, after the G code file that postposition obtains was input to lathe, there was certain deviation in the part shape that processing obtains with design; Influence the part processing quality, when serious processing parts is scrapped.

Summary of the invention:

The objective of the invention is to problem to present existence; Provide a kind of and consider that the multi-axis numerical control of machine tool structure error processes rearmounted disposal route; Through position and the attitude misalignment considering to exist between the machine tool motion component, each coordinates of motion that postposition is handled in the G code that obtains compensate, the error that position between the elimination machine tool motion component and attitude misalignment bring to cutting tool path; Improve the machine tool kinematic accuracy, satisfy the part processing quality requirements.

Realize that the concrete technical scheme that the object of the invention adopted is following:

A kind ofly consider that the multi-axis numerical control of machine tool structure error processes rearmounted disposal route, comprise following steps:

(1) set up the machine tool motion transformation chain that does not contain structural failure, the machine tool motion chain comprises that cutter is to machine tool motion chain Q _MTArrive machine tool motion chain T with workpiece _WM, cutter cutter location direction vector and position obtain the direction vector P of processing stand on the workpiece through motion converter _WWith position vector U _W, relation is shown in following system of equations:

$\left\{\begin{array}{c}{T}_{\mathrm{MW}}{\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

Q wherein _MTBe the transformation matrix of cutter with respect to bed piece, T _MWBe the transformation matrix of workpiece with respect to bed piece.

X, Y, the small translation Δ X of Z axle, Δ Y, Δ Z and along X, Y, the minor rotation Δ A of Z axle, Δ B, Δ C can obtain j moving component to i moving component error transform battle array Δ Q _Ij:

Consider under the situation of machine tool structure error that (two) each motion parts of lathe exists along X, Y, the small translation Δ X of Z axle, Δ Y, Δ Z and along X, Y, the minor rotation Δ A of Z axle, Δ B, Δ C can obtain the error transform battle array:

${\mathrm{\ΔQ}}_{i,j}=\left[\begin{array}{cccc}0& -\mathrm{\ΔC}& \mathrm{\ΔB}& \mathrm{\ΔX}\\ \mathrm{\ΔC}& 0& -\mathrm{\ΔA}& \mathrm{\ΔY}\\ -\mathrm{\ΔB}& \mathrm{\ΔA}& 0& \mathrm{\ΔZ}\\ 0& 0& 0& 0\end{array}\right]$

After considering the machine tool structure error, the machine tool motion transformation chain that obtains in the step () then converts the machine tool motion transformation chain that contains structural failure into, shown in following system of equations.

$\left\{\begin{array}{c}{T_{\mathrm{MW}}^{\′}\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}^{\′}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

(3) adopt the machine tool motion transformation chain to find the solution each kinematic axis ideal movements coordinate of tool motion.

According to the machine tool motion transformation chain that does not contain structural failure that obtains in (), find the solution two adjacent cutter location (initial cutter location CL in the cutter location source file ₀With target cutter location CL _d) between the motion desired axis coordinates of motion Δ ₀

(4) adopt the machine tool motion transformation chain that contains structural failure to calculate the compensation rate of above-mentioned ideal movements coordinate; Through compensating this ideal movements coordinate; Make lathe the actual motion track and set deviation between the movement locus within allowed band, guarantee cutter actual path and the consistance of setting track

(1) with desired axis coordinates of motion Δ ₀Bring the machine tool motion transformation chain that contains the machine tool structure error in the step (two) into, obtain the actual position that arrives after each motion of lathe, promptly actual cutter location CL _{D, k}, this moment k=1.

The machine tool motion transformation chain that does not contain structural failure of the middle acquisition that (2) obtains according to () is found the solution initial cutter location CL ₀With actual cutter location CL _{D, k}Between the motion desired axis coordinates of motion Δ _k

(3) calculate initial cutter location CL ₀With actual cutter location CL _{D, k+1}Between ideal movements axial coordinate Δ _K+1

(4) if | Δ k+1-Δ k|＜δ (δ for set axle coordinates of motion permissible error), then forward to (five), otherwise forward (1) to, the k value in (1) increases 1.

(5) the initial cutter location CL of output ₀With target cutter location CL _dBetween the final axle coordinates of motion of motion be:

Δ=Δ ₀+ d Δ _kCan obtain to comprise the rearmounted result of lathe of machine tool structure error through above-mentioned steps.

Wherein, the concrete performing step of (3) is following in above-mentioned (four) step:

(3.1) in order to compensate actual cutter location CL _{D, k}With target cutter location CL _dBetween deviation, need be on the desired axis coordinates of motion compensating shaft coordinates of motion increment d Δ _k, the d Δ _kExpression formula following:

dΔ _k＝Δ ₀-Δ _k

With the d Δ _kCompensate to Δ ₀On, then the axle coordinates of motion after the compensation are following:

Δ _d，k＝Δ ₀+dΔ _k

(3.2) the axle coordinates of motion Δ after will compensating _{D, k}Bring the machine tool motion transformation chain that contains the machine tool structure error in (two) into, obtain the actual position that arrives after each motion of lathe, promptly actual cutter location CL _{D, k+1}

The machine tool motion transformation chain that does not contain structural failure of the middle acquisition that (3.3) obtains according to () is found the solution initial cutter location CL ₀With actual cutter location CL _{C, k+1}Between the motion desired axis coordinates of motion Δ _K+1

The present invention is the basis with machine tool motion transformation chain and kinematic error battle array, sets up a kind of rearmounted disposal route that contains the machine tool structure error.This model has been considered the influence of machine tool structure error to the machine tool motion precision; Set up the machine tool motion transformation chain that contains the machine tool structure error; Be the basis with this motion converter chain then; Through calculating since the postposition that structural failure causes handle in each coordinates of motion compensation rate, it is compensated in the G code in each amount of exercise, form in rearmounted the processing in each coordinates of motion.

The rearmounted disposal route that contains the machine tool structure error that the present invention set up; Its useful achievement is: the present invention has remedied the weak point of only considering machine tool motion component ideal position relation in the general rearmounted disposal route, can realize containing the rearmounted disposal route of machine tool structure error; Be applicable to the rearmounted processing of arbitrary structures gang tool, have good universality; Adopt the present invention can effectively improve the machine tool motion precision, improve the processing parts quality, and need not append any equipment investment, possess good application prospects.

Description of drawings:

Fig. 1 processes rearmounted processing flow chart for the multi-axis numerical control of considering the lathe geometry error.

Fig. 2 is the process flow diagram of " the machine tool motion transformation chain that employing contains structural failure calculates the compensation rate of above-mentioned ideal movements coordinate " among Fig. 1.

Fig. 3 is the process flow diagram that " calculates ideal movements axial coordinate between preliminary examination cutter location and the actual cutter location " among Fig. 2.

Embodiment:

Below in conjunction with accompanying drawing and specific embodiment the present invention is described further.

The multi-axis numerical control of consideration lathe geometry error is processed rearmounted disposal route, comprises following method:

(1) relative position relation between each moving component of multi-axis numerical control lathe is carried out analysis to measure; Set up the machine tool motion transformation chain that does not contain the machine tool structure error; The machine tool motion chain that does not contain the machine tool structure error comprise cutter to machine tool motion chain and workpiece to the machine tool motion chain; Cutter cutter location direction vector and position vector obtain the direction vector and the position vector of processing stand on the workpiece through motion converter, and this kinematic chain computing formula is shown in following system of equations:

$\left\{\begin{array}{c}{T}_{\mathrm{MW}}{\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

Q wherein _MTBe the transformation matrix of cutter to the machine tool motion chain, T _MWBe the transformation matrix of workpiece to the machine tool motion chain, [0010] ^TBe cutter cutter location position vector, [0001] ^TBe cutter cutter location direction vector, U _WBe cutter location position vector on the workpiece, P _WIt is cutter location direction vector on the workpiece

Concrete performing step is following:

1. set up the transformation matrix Q of cutter to the machine tool motion chain _MT, this transformation matrix computing formula is following:

Q _MT＝Q _M，n×…×Q _i，j×…×Q _1，T

Q wherein _{M, n}Be cutter in machine tool motion chain n moving component is to the motion converter matrix of bed piece, Q _{I, j}Be cutter in machine tool motion chain j moving component is to the motion converter matrix of i moving component, Q _{1, T}The transformation matrix of 1 kinematic chain of cutter to that is cutter in the machine tool motion chain, above-mentioned Q _{M, n}, Q _{I, j}And Q _{1, T}Three types of transformation matrix reflection lathe different motion parts relative position relations, this matroid can be derived through the machine tool motion model.

2. set up transformation matrix T from workpiece to the machine tool motion chain _MW, this transformation matrix computing formula is following:

T _MW＝T _M，n×…×T _i，j×…×T _1，W

T wherein _{M, n}Be workpiece in machine tool motion chain n moving component is to the motion converter matrix of bed piece, T _{I, j}Be workpiece in machine tool motion chain j moving component is to the motion converter matrix of i moving component, T _{1, W}The transformation matrix of 1 kinematic chain of cutter to that is workpiece in the machine tool motion chain

Above-mentioned T _{M, n}, T _{I, j with}T _{1, W}Three types of transformation matrix reflection lathe different motion parts relative position relations, this matroid can be derived through the machine tool motion model.

3. with the transformation matrix Q that obtains in 1 and 2 steps from cutter to the machine tool motion chain _MTWith transformation matrix T from workpiece to the machine tool motion chain _MWBring following system of equations into

$\left\{\begin{array}{c}{T}_{\mathrm{MW}}{\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

Can set up the machine tool motion chain that does not contain the machine tool structure error.

(2) relative motion position deviation between each moving component of multi-axis numerical control lathe is measured, set up error transform battle array Δ Q from j moving component to i moving component _{I, j}:

${\mathrm{\ΔQ}}_{i,j}=\left[\begin{array}{cccc}0& -\mathrm{\ΔC}& \mathrm{\ΔB}& \mathrm{\ΔX}\\ \mathrm{\ΔC}& 0& -\mathrm{\ΔA}& \mathrm{\ΔY}\\ -\mathrm{\ΔB}& \mathrm{\ΔA}& 0& \mathrm{\ΔZ}\\ 0& 0& 0& 0\end{array}\right]$

Wherein Δ X, Δ Y, Δ Z be each motion parts of lathe respectively along X, Y, the small translation of Z axle, Δ A, Δ B, Δ C be each motion parts of lathe respectively along X, Y, the minor rotation of Z axle, Δ Q _{I, j}Be 4 * 4 rank error transform battle arrays, reflect each motion parts of lathe along X, Y, the composition error of Z axle.

After considering the machine tool structure error, set up the machine tool motion transformation chain that contains structural failure, this kinematic chain computing formula is shown in following system of equations:

$\left\{\begin{array}{c}{T_{\mathrm{MW}}^{\′}\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}^{\′}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

Q ' wherein _MTBe to contain the transformation matrix of the cutter of structural failure to the machine tool motion chain, T ' _MWBe to contain the transformation matrix of the workpiece of structural failure to the machine tool motion chain, [0010] ^TBe cutter cutter location position vector, [0001] ^TBe cutter cutter location direction vector, U _WBe processing stand position vector on the workpiece, P _WIt is processing stand direction vector on the workpiece.

Concrete performing step is following:

1. set up and contain the transformation matrix Q of the cutter of structural failure to the machine tool motion chain _MT, this transformation matrix computing formula is following:

Q′ _MT＝(E+ΔQ _M，n)×Q _M，n×…×(E+ΔQ _i，j)

×Q _i，j×…×(E+ΔQ _1，T)×Q _1，T

Q wherein _{M, n}Be cutter in machine tool motion chain n moving component is to the motion converter matrix of bed piece, Q _{I, j}Be cutter in machine tool motion chain j moving component is to the motion converter matrix of i moving component, Q _{1, T}The transformation matrix of 1 kinematic chain of cutter to that is cutter in the machine tool motion chain, E is a unit matrix; Δ Q _{M, n}Be that cutter is to the error transform battle array of machine tool motion chain from n moving component to lathe, Δ Q _{I, j}Be that cutter is to the error transform battle array of machine tool motion chain from j moving component to i moving component, Δ Q _{1, T}It is the error transform battle array of cutter 1 moving component to the machine tool motion chain from cutter to the.

Above-mentioned Q _{M, n}, Q _{I, i-1}And Q _{1, T}Three types of transformation matrix reflection lathe different motion parts relative position relations, this matroid can be derived above-mentioned Δ Q through the machine tool motion model _{M, n}, Δ Q _{I, j}, Δ Q _{1, T}Three error transform squares all are to reflect machine tool motion component along X, Y, and the composition error of Z axle can be through measuring foundation to relative motion position deviation between each moving component of multi-axis numerical control lathe.

2. set up and contain the transformation matrix T ' of the workpiece of structural failure to the machine tool motion chain _MW, this transformation matrix computing formula is following:

T′ _MW＝(E+ΔT _M，n)×T _M，n×…×(E+ΔT _i，j)

×T _i，j×…×(E+ΔT _1，W)×T _1，W

T wherein _{M, n}Be workpiece in machine tool motion chain n moving component is to the motion converter matrix of bed piece, T _{I, j}Be workpiece in machine tool motion chain j moving component is to the motion converter matrix of i moving component, T _{1, w}The transformation matrix of 1 kinematic chain of cutter to that is workpiece in the machine tool motion chain, E is a unit matrix; Δ T _{M, n}Be that workpiece is to the error transform battle array of machine tool motion chain from n moving component to lathe, Δ T _{I, j}Be that workpiece is to the error transform battle array of machine tool motion chain from j moving component to i moving component, Δ T _{1, W}It is the error transform battle array of workpiece 1 moving component to the machine tool motion chain from workpiece to the; Above-mentioned T _{M, n}, T _{I, j}And T _{1, W}Three types of transformation matrixs all are reflection lathe different motion parts relative position relations, and this matroid can be derived above-mentioned Δ T through the machine tool motion model _{M, n}, Δ T _{I, j}, Δ T _{1, W}Three error transform battle arrays reflect machine tool motion components along X, Y, and the composition error of Z axle can be through measuring foundation to relative motion position deviation between each moving component of multi-axis numerical control lathe.

Above-mentioned T _{M, n}, T _{I, j}And T _{1, W}Three types of transformation matrixs all are 4 * 4 rank transformation matrixs of reflection lathe different motion parts relative position relation, and this matroid can be derived above-mentioned Δ T through the machine tool motion model _{M, n}, Δ T _{I, j}, Δ T _{1, W}Three error transform squares all are to reflect machine tool motion component along X, Y, and the composition error of Z axle can be through measuring foundation to relative motion position deviation between each moving component of multi-axis numerical control lathe.

3. with the transformation matrix Q ' that contains structural failure that obtains in 1 and 2 steps from cutter to the machine tool motion chain _MTWith the transformation matrix T ' that contains structural failure from workpiece to the machine tool motion chain _MWBring following system of equations into

$\left\{\begin{array}{c}{T_{\mathrm{MW}}^{\′}\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}^{\′}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

Can set up the machine tool motion chain that contains the machine tool structure error.

(3) adopt the machine tool motion transformation chain that does not contain structural failure to find the solution each kinematic axis ideal movements coordinate of tool motion

According to the machine tool motion transformation chain that does not contain structural failure that obtains in (), find the solution two adjacent cutter location (initial cutter location CL in the cutter location source file ₀With target cutter location CL _d) between the motion desired axis coordinates of motion Δ ₀, initial cutter location CL ₀With target cutter location CL _dRelevant information can obtain from G code.

(4) adopt the machine tool motion transformation chain that contains structural failure to calculate the compensation rate of the above-mentioned ideal movements coordinate of motion calculation; Through compensating this ideal movements coordinate; Make lathe the actual motion track and set deviation between the movement locus within allowed band, guarantee cutter actual path and the consistance of setting track.

(1) with desired axis coordinates of motion Δ ₀Bring the machine tool motion transformation chain that contains the machine tool structure error in (two) into, obtain the actual position that arrives after each motion of lathe, promptly actual cutter location CL _{D, k}, this moment k=1.

(2) according to the machine tool motion transformation chain that does not contain structural failure that obtains in (), find the solution initial cutter location CL ₀With actual cutter location CL _{D, k}Between the motion desired axis coordinates of motion Δ _k

(3) calculate initial cutter location CL ₀With actual cutter location CL _{D, k+1}Between ideal movements axial coordinate Δ _K+1

(4) if | Δ _K+1-Δ _k|＜δ (the axle coordinates of motion permissible error of δ) for setting, then forward to (five), otherwise forward (1) to, the k value in (1) increases 1.

Above-mentioned flow process is as shown in Figure 2, and the part among Fig. 2 in the frame of broken lines is the input and output of this flow process, and is corresponding with flow process (three) and (five).

(5) the initial cutter location CL of output ₀With target cutter location CL _dBetween the final axle coordinates of motion of motion be:

Δ＝Δ ₀+dΔ _k

Wherein, the concrete performing step of (3) is following in above-mentioned (four) step:

1) in order to compensate actual cutter location CL _{D, k}With target cutter location CL _dBetween deviation, need be on the desired axis coordinates of motion compensating shaft coordinates of motion increment d Δ _k, the d Δ _kExpression formula following:

dΔ _k＝Δ ₀-Δ _k

With the d Δ _kCompensate to Δ ₀On, then the axle coordinates of motion after the compensation are following:

Δ _d，k＝Δ ₀+dΔ _k

2) the axle coordinates of motion Δ after will compensating _{D, k}Bring the machine tool motion transformation chain that contains the machine tool structure error in (two) into, obtain the actual position that arrives after each motion of lathe, promptly actual cutter location CL _{D, k+1}

The machine tool motion transformation chain that does not contain structural failure of the middle acquisition that 3) obtains according to () is found the solution initial cutter location CL ₀With actual cutter location CL _{C, k+1}Between the motion desired axis coordinates of motion Δ _K+1

Can obtain to comprise the rearmounted result of lathe of machine tool structure error through above-mentioned steps.

This part flow process is as shown in Figure 3, and wherein the part in the frame of broken lines is the input and output of this flow process, and is corresponding with step 2 and step 4 in the flow process (four).

Whole flow process can be represented through Fig. 1.

Claims (3)

1. a multi-axis numerical control of considering the machine tool structure error is processed rearmounted disposal route, comprises the steps:

(1) set up the machine tool motion transformation chain, this machine tool motion chain comprises that cutter is to machine tool motion chain Q _MTArrive machine tool motion chain T with workpiece _WM, the direction vector P of cutter cutter location direction vector and position processing stand on the workpiece that motion converter obtains _WWith position vector U _W, relation is shown in following system of equations:

$\left\{\begin{array}{c}{T}_{\mathrm{MW}}{\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

(2) find the solution each kinematic axis ideal movements coordinate of tool motion according to the machine tool motion transformation chain:, find the solution that two adjacent cutter locations are initial cutter location CL in the cutter location source file according to the machine tool motion transformation chain that obtains in the step (1) ₀With next cutter location CL _dBetween the motion desired axis coordinates of motion Δ ₀

(3) according to each motion parts of lathe exist along X, Y, the small translation Δ X of Z axle, Δ Y, Δ Z; And along X; Y, the minor rotation Δ A of Z axle, Δ B, Δ C, try to achieve any j the moving component of lathe to i moving component error transform battle array error transform battle array:

${\mathrm{\ΔQ}}_{i,j}=\left[\begin{array}{cccc}0& -\mathrm{\ΔC}& \mathrm{\ΔB}& \mathrm{\ΔX}\\ \mathrm{\ΔC}& 0& -\mathrm{\ΔA}& \mathrm{\ΔY}\\ -\mathrm{\ΔB}& \mathrm{\ΔA}& 0& \mathrm{\ΔZ}\\ 0& 0& 0& 0\end{array}\right]$

The machine tool motion transformation chain that then obtains in the step (1) then converts the machine tool motion transformation chain that contains structural failure into, shown in following system of equations:

$\left\{\begin{array}{c}{T_{\mathrm{MW}}^{\′}\left[\begin{array}{cc}{U}_W& 0\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 1& 0\end{array}\right]}^T\\ T_{\mathrm{MW}}^{\′}{\left[\begin{array}{cc}{P}_W& 1\end{array}\right]}^T=Q_{\mathrm{MT}}^{\′}{\left[\begin{array}{cccc}0& 0& 0& 1\end{array}\right]}^T\end{array}\right.$

Wherein, Q ' _MTBe to contain the transformation matrix of the cutter of structural failure to the machine tool motion chain, T ' _MWBe to contain the transformation matrix of the workpiece of structural failure to the machine tool motion chain.

(4) calculate the compensation rate of above-mentioned ideal movements coordinate based on the above-mentioned machine tool motion transformation chain that contains structural failure; Then based on this ideal movements coordinate of gained compensation rate compensation, make deviation between actual motion track and the setting movement locus of lathe within allowed band;

(5) the initial cutter location CL of output ₀With target cutter location CL _dBetween the final axle coordinates of motion of motion be:

Δ＝Δ ₀+dΔ _k

Can obtain to comprise the rearmounted result of lathe of machine tool structure error through above-mentioned steps.

2. multi-axis numerical control according to claim 1 is processed rearmounted disposal route, it is characterized in that, described step (4) detailed process is:

(4.1) with desired axis coordinates of motion Δ ₀The machine tool motion transformation chain that contains the machine tool structure error in the substitution step (3) is obtained the actual position that arrives after each motion of lathe, promptly actual cutter location CL _{D, k}, k=1 when getting into this step (4.1) for the first time;

(4.2) the machine tool motion transformation chain that obtains according to step (1) is found the solution initial cutter location CL ₀With actual cutter location CL _{D, k}Between the motion desired axis coordinates of motion Δ _k

(4.3) calculate initial cutter location CL ₀With actual cutter location CL _{D, k+1}Between ideal movements axial coordinate Δ _K+1

(4.4) if | Δ k+1-Δ k|＜δ then forward step (5) to, otherwise the k value jumps to step (1) double counting after increasing 1, wherein the axle coordinates of motion permissible error of δ for setting.

3. multi-axis numerical control according to claim 2 is processed rearmounted disposal route, it is characterized in that, the detailed process of described step (4.3) is following:

(4.3.1) compensating shaft coordinates of motion increment d Δ on the desired axis coordinates of motion _k,, to compensate actual cutter location CL _{D, k}With target cutter location CL _dBetween deviation:

dΔ _k＝Δ ₀-Δ _k

With the d Δ _kCompensate to Δ ₀On, the axle coordinates of motion Δ after then compensating _{D, k}As follows:

Δ _d，k＝Δ ₀+dΔ _k

(4.3.2) the axle coordinates of motion Δ after will compensating _{D, k}Bring the machine tool motion transformation chain that contains the machine tool structure error in the step (3) into, obtain the actual position that arrives after each motion of lathe, promptly actual cutter location CL _{D, k+1}

The machine tool motion transformation chain that does not contain structural failure of the middle acquisition that (4.3.3) obtains according to step (1) is tried to achieve initial cutter location CL ₀With actual cutter location CL _{C, k+1}Between the motion desired axis coordinates of motion Δ _K+1

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